1. Field of the Invention
This invention relates generally to semiconductor testing and, more particularly, to a method and apparatus for evaluating the potential failure of semiconductor chips by digitizing a video scene of only strategic areas on said chip and comparing the resulting pattern with an acceptable pattern stored in memory.
2. Description of the Prior Art
The use of pattern recognition techniques is known in the art of testing semiconductor die. Pattern recognition systems are being used for automatic die inspection in an attempt to locate gross defects in the die. This may be accomplished since the defects can alter a digitized video scene. In some cases, the semiconductor die is scanned and the digitized video signal from a T.V. camera is compared with acceptable stored data.
Unfortunately, to scan an entire die including portions of the scribe areas surrounding the die results in a great deal of data which must be stored and processed. This not only substantially increases the complexity of the test equipment, but also significantly increases test time. The need existed to develop a semiconductor die testing apparatus which would be accurate and have relatively fast test time.